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ThisEndUp
04-22-2009, 06:13 AM
Those of you who have pulled out your thermostats....
What size restriction did you put in/on the bike to reduce the coolant flow?

I pulled the metal thermostat from the black plastic housing and am going to give that a try. It's a 7 or 8mm hole, if I remember correctly.

I'd like to get somewhere in the ballpark with the restrictor size. Then just tape up the radiator as necessary to further adjust temp.

Any advice?

Noassmblyrqired
04-22-2009, 01:21 PM
I was putting some thought into the flow restrictor myself. The restriction does not have to be located in the head like the thermostat because it does not need to be thermally linked to the head. So....the restriction could be anywhere in the cooling loop. Like inline with one of the cooling hoses to (or from) the radiator. It would be quite easy to slide in a smaller piece of hose, a plastic, brass, or aluminum plug into the radiator hose. This also means you could use a "variable" or "ajustable" restriction such as a butterfly or ball valve.

What kind of gauges are available to read water temp at the head besides automotive type gauges? I have some old autometer junk, but would like something a little smaller and more elegant. I need a suggestion!

kanerdog1x1
04-22-2009, 01:24 PM
my bike is running with no restrictor or thermostat, but i use ALOT of tape on the rad. at the moment there is only 1/4 of the tubes and fins surface area exposed.

ThisEndUp
04-22-2009, 03:44 PM
my bike is running with no restrictor or thermostat, but i use ALOT of tape on the rad. at the moment there is only 1/4 of the tubes and fins surface area exposed.

I tried that. I can't get enough heat into the engine to safely set off in motion.

ThisEndUp
04-22-2009, 03:48 PM
I was putting some thought into the flow restrictor myself. The restriction does not have to be located in the head like the thermostat because it does not need to be thermally linked to the head. So....the restriction could be anywhere in the cooling loop. Like inline with one of the cooling hoses to (or from) the radiator. It would be quite easy to slide in a smaller piece of hose, a plastic, brass, or aluminum plug into the radiator hose. This also means you could use a "variable" or "ajustable" restriction such as a butterfly or ball valve.

What kind of gauges are available to read water temp at the head besides automotive type gauges? I have some old autometer junk, but would like something a little smaller and more elegant. I need a suggestion!

Yeah, I tried the tube stuffer option and may still go back to that, for ease of changing restrictor I.D.. Although now I have a new problem.....coolant is getting into my combustion chamber. Fuuuuuuuuuuudddddgggggee.....'Going to be a long night.
I'm starting to think this bike is cursed (or I'm an idiot :happy: ). Air cooled two strokes were so much easier....

Gman2005
04-23-2009, 04:41 PM
you don't need to put anything in there mate, its not meant to be there anyway, its only aprilia who add it for the bikes.

ThisEndUp
04-24-2009, 06:05 AM
you don't need to put anything in there mate, its not meant to be there anyway, its only aprilia who add it for the bikes.

I hear you. The water leak into the combustion chamber was dropping the temp down. Runs fine now that it's sorted out. Runs fine with no restriction added.

:cheers:

Off I go for a full weekend at the track. Summer like weather is expected.
That deserves a dancing banana.. :banana:

19E-299
05-22-2009, 09:20 AM
Those of you who have pulled out your thermostats....
What size restriction did you put in/on the bike to reduce the coolant flow?

I pulled the metal thermostat from the black plastic housing and am going to give that a try. It's a 7 or 8mm hole, if I remember correctly.

I'd like to get somewhere in the ballpark with the restrictor size. Then just tape up the radiator as necessary to further adjust temp.

Any advice?

trackbike?

Micah / AF1 Racing
05-24-2009, 07:35 PM
Thermostats are a genius invention, helping to keep the motor alive for long periods of time. I have gone so far as to put them into bikes that did not come with them for track use....

Hell, KTM's GP bikes do not use a thermostat, but rather a temperature sensor controlled electric water pump to get the same effect....if such things are done on GP bikes to keep engine temps as consistent as possible what or why would you want to go back to pre 1900's engine cooling technology?

ThisEndUp
05-25-2009, 07:30 AM
Yes, trackbike.

....and as previously stated, bike runs fine without any restrictor.

:cheers: